LECTURE 14: CEREBELLUM Flashcards
what is considered the “great comparator”
the cerebellum
what unconsciously adjusts posture and coordinates movements
cerebellum
when intending to move the cerebelum processess info from ___ lobes together with the ___ receptors, proprioceptors, motor activity of ___ and ___ horn cells of SC
frontal
vestibular
brainstem and ventral
what does the cerebellum do when we are actually moving
compares the intended vs actual movements to make needed adjustments
what is cerebellar white matter called
arbor vitae
how many hemispheres does the cerebellum have
2
cerebellum = ___ of total brain volume but has almost ___ the number of neurons as cerebral cortex
10%
4x
the cerebellum has inner ___ white matter regions that transmitts ____/___ info
myelinated
afferent/efferent
there are no ___ connections between the cerebellum and ___ neurons`
direct
motor
there are no direct connections between the cerebellum and motor neurons, all are via the motor tract cell bodies in motor ___ , ___ ___ , and ___
cortex
premotor cortex
brainstem
lots of sensory info ____ the cerebellum
enters
cerebellum is invovled in the learning of what
timing , rhythm , synchronization of movements and how to correct motor errors
does serve damage to the cerebellum causes direct muscle weakness or sensory perception issues???
nauuuurrrr bc it causes coordination and postural control deficits ( some decreased cognitive and emotional function)
what are the cerebellar structures -3s
3 cerebellar peduncles
3 cortical layers
3 deep cerebellar nuclei
3 lobes
3 vertical divisions
3 functional; divisions
what are the 3 cerebellar peduncles
superior
middle
inferior
what are the 3 cortical layers
molecular
purkinje
granular
whar are the 3 deep cerebellar nuclei
dentate
interposed
- emboliform
- globuse
fastigial
what are the 3 lobes of the cerebellar
anterior
posterior
flocculonodular
what are the 3 vertical divisions of the cerebellar
midline vermis
paravermis/intermediate part
lateral hemisphere
what are the 3 functiona; divisions
vestibulo cerebellum
spino cerebellum
cerebro cerebellum
the superior cerebellar peduncles is mostly ___
efferents
the middle cerebellar peduncles is mostly ___
afferents
the inferior cerebellar peduncles is mostly what
afferents and efferents
the superior cerebellar peduncles is projections to motor nuclei of the ___ , relaying signal to ___ in primary and premotor cortices
thalamus
UMN
which cerebellar peduncle projects to the red nucleus
superior
afferents from the superior cerebellar peduncles come from which tract
anterior spinocerebellar tract
middle cerebellar peduncles has projections arising from _____ pontine nuclei from ___ cortex and ____ colliculus
contralateral
cerebral
superior
where does the afferents arise from in the inferior cerebellar peduncles
vestibular apparatus/nuclei , SC and inferior olivary nucleus
where does the efferents project to from in the inferior cerebellar peduncles
vestibulospinal and reticulospinal tracts
what kind of matter are the 3 cortical layers of the cerebellar
gray matter
what does the molecular and granular layers of the cerebellar have
interneurons , including granule , golgi , stellate and basket cells
the purkinje layers of the cerebellar cortex has what kind of cell bodies
purkinje
what doe the purkinje cells inhibit
cerebellar and vestibular nuclei
which fibers transmit afferent excitatory neurotransmitters in the cerebellar cortex
mossy and climbing fibers
where does mossy fibers start and where does it transmit and into where
starts in pons adn SC
transmitts somatosensory , arousal , balance and cerebral cortex info into the cerebellum
where does climbing fibers start and where does it transmit and into where
start in the inferior olivary nucleus
transmits movements erros into cerebellum
what is the order of the layers in te cerebellar cortex from superficial to deep
molecular
purkinje
granule
what is the functional unit of the cerebellar cortex
purkinje cell (inhibitory) + deep nuclear cell ( excitatory)
what is in the deep nuclei of the cerebellar cortex most lateral to medial (Dont Eat Greasy Food)
Dentate
interposed
- Emboliform
- Globose
Fastigial
what cells are among the largest cells of the brain with huge dendritic branching
purkinje cells
all cerebellar output is transmitted thru the ___ cells
purkinje
what is the most lateral deep cerebellar nuclei
dentate
what is most medial deep cerebellar nuclei
fastigial
what is the fucntion of the vestibulocerebellum (flocculonodular lobe)
balance and eye movements
what zone is lateral vestibular nucleus and apparatus in?
vestibulocerebellum (flocculonodular lobe)
what functional region of the cerebellar is the onyl part of cerebellum receiving input directly from the SC
spinocerebellum (vermis and intermediate zones)
what lies proximal in the spinocerebellum zone of the cerebellum?
fastigial nuclei (vermis)
what lies distal in the spinocerebellum zone of the cerebellum
interposed nuclei (intermediate zone)
what is the function of the fastigial nuclei that is in the spinocerebellum region of the cerebellum
proximal gross movements of body and limb
what is the function of the interposed nuclei that is in the spinocerebellum region of the cerebellum
distal voluntary movement (limbs)
which functiona region of the cerebellum is the dentate nuclei in
cerebrocerebellum (lateral hemi)
what does the cerebrocerebellum zone of the cerebellum regulate
highly skilled movements
the cerebrocerebellum zone of the cerebellum regulates highly skilled movements like what
motor planning , cognitive aspects and working memory
also execution of complex spatial and temporal sequences of movements , regulating cortical motor programs
the vestibulocerebellum/ flocclonodular lobe controls ___ and ___/___ muscles
eyes and prox trunk muscles
the vestibulocerebellum/ flocclonodular lobe is important for what
balance/ equilibrum
the vermis part of the spiniocerebellum controls ___ and ___/___ muscles
eyes and prox trunk
the intermediate zone/ paravermal zone of the spiniocerebellum controls what
distal limb muscles
what is the cerebrocerebellum zone (lateral zone) important for
motor planning
the superior cerebllar artery supplies the what
supeiror and middle cerebellar peduncles and interpedunclar region
what does the anterior inferior cerebllar artery supplie
middle cerebellar peduncle , anterior inferior cerebellum including the flocculus
what supplies the tonsils, inferior vermis, inferior cerebellar peduncle and inferir aspects of the cerebellar hemispheres
posterior inferior cerebellar artery
what is the input for the vestibulocerebellum region
ipsilateral vestibular nuclei / apparatus and visual cortex
where does the synaspe occur in the vestibulocerebellum zone
flocculonodular lobe
where does the output of the vestibulocerebellum project to
vestibular nuclei
the out put of the vestibulocerebellum projects to the vestibular nuclei and controls posture by the ___ and ___ ____ tracts and also controls ___ movements
lateral and medial vestibulospinal tracts
eye
do the spinocerebellar tracts cross ?
no
the spinocerebellar tracts is a high ___ pathways- with __ neurons transmitting ___ to cerebellum
fidelity
2
ipsilaterally
in the spinocerebellar tract the 1st order proprioceptors transmits info from ___ and ___ trunk to SC ___ ___ of the dorsal column to synapse in the gray matter nucleus of ____ nucleus (T1-L2)
LE
lower
fasciculus gracilis
clarkes
the 2nd order axon of the spinocerebllar tract composes ___ ___ pathway which stays ____ , and going into the ___ ___ ___ to cerebellar cortex .. does it cross?
posterior spinocerebellar pathway
stays ipsilateral
inferier cerebellar peduncle
doesnt cross
in the cunocerebellar tract the 1st order ___ start from proprioceptors in the ___ , ___ and __ trunk and go thru the _fasiciculus ___ of dorsal columns of lower ___
afferents
neck , UE and upper trunk
cuneatus
medulla
in the cuneocerebellar tract the synapse happens in the ___ ___ nucleus in the lower ___ to form the ____ pathway in the medulla … it stays ___ and enters the ____ ___ ___ to the cerebellar cortex .. does it cross?
lateral cuneate nucleus
medulla
cuneocerebellar
ipsilateral
inferior cerebellar peduncles
does not cross
the internal feedback tracts of the spinocerebellum monitor what
spinal internruon activity
proprioceptive input
SC reflex activity
descending motor commands
single neuron of anterior spinocerebllar tract begins in the ___ ___ matter and crosses and travels up the ___ anterior spinocerebllar tract to the ___
TL gray matter
contralateral
midbrain
the ant spiniocerebellar tract divides with most crossing at the ___ and entering the ___ ____ ___ - double cross
midbrain
contralteral superior CP
eve tho most cross at the midbrain for the ant spinocerebellar tract come stay ipsilateral entering ___ ___ ___
ipsilateral superior CP
during the anterior spinocerebellar tract each cerebellar hemisphere get inputs from ___ sides of the ___ body
both
lower
the rostrospinocerebellar tract starts in the __ matter or cervical SC to __ cerebellum thru the ___ and __ cerebellar peduncles
T1
ipsilateral
inferior and supperir
for the outputs of the spinocerebellum the ___ ___ project to deep nuclei
purkinje cells
for the outputs of the spinocerebellum the vermis to ___ ___ tracts
medial motor
for the outputs of the spinocerebellum the ____ zone to lateral motor tracts
intermediate
do any of the outputs of the spinocerebellum directly transmit from cerebellum to motor tracts
no
the vermis part of the output of the spinocerebellum is when the purkinje cells project to ___ nuclei of the vermis then the ___ and cerebral cortex via the ___
fastigial
brainstem
thalamus
the intermediate zone part of the output of the spinocerebellum is when the purkinje cells project to the ___ nuclei , providing inputs to the ___ , cerebral cortex to ____ and ____ systmes to control more ___ muscles of limbs and digits
interposed
thalamus
corticospinal and rubrospinal
distal
closed cerebro cerebello cerebral loop is when motor and premotor cortices going to ___ nuclei to ___ ___ cortex to ___ nucleus to ___ and back to cerebral cortex
pontine
lateral cerebellar
dentate
thalamus
the input of the cerebrocerebellar circuits consist of lots of ____ cortex info into the __ which then cross and enter the ___ CP into the lateral cerebellar cortex
cerebral
pons
middle
the out put of the cerebrocerebellar circuits consists of the ____ of the lateral cerebellar cortex to synapse with the ___ nucleus and then the ___ leave via the __- CP and then ___ and go to the ___ and synapse and go the the cerebral cortex
purkinjes
dentate
efferents
superior
cross
thalamus
the cerebrocerebellar circuts are involved with what
motor planning and timing of movements
changes in the neural activity i n the dentat starts ___ that of the cerebral cortex ___ to execution of movement
before
prior
does the cerebral cortex directly project to the cerebellum
no
inputs into the cerebellum go to the cerebral cortex and synapse where
on the ipsilateral pontine nuclei
inthe cerebral cortex the ____ ____ fibers project to contralteral cerebrocerebellum via the ___ CP
transverse pontocerebellar
middle
the vestibular nuclie is CN ___ and in the __
VIII
pons
the vestibular nuclei project where ? via what ?
vestibulocerebellum via the inferior cerebellar peduncle
what 2 tracts are apart of the spinal cord fo the inputs of the cerebellum
dorsal spinocerebellar and cuneocerebellar tracts
where is the trigeminal mesencephalic nucleus
spinal cord
pertaining to the inputs of the cerebellum , the SC projects where? via what?
projects to the spinocerebellum via the inferior cerebellar peduncle
pertaining to the inputs to the cerebellum the inferior olivary nuclei projects via what
inferior cerebellar peduncle
the vestibulocerebellum receives input from what and sends out put where
receives from vestibular apparatus and nuclei
sends to vestibualr nuclei
unilateral cereballr conditions causes impairments on ___ side of body
ipsilateral
why do unilateral cereballr conditions causes impairments on ipsilateral side of body
-spinocerebellar afferent arise from ipsi sources
-most cerbellar efferents to motor tracts remain ipsi
-cerebellar efferents cross on the way to contra cerebral cortex and red nucleus with related descending tracts crossing so double cross
signs of cerebellar dysfunction in any /all areas is what
Ataxia
what is ataxia
jerky , uncoordinated movements of trunk/neck and limbs
can there by normal strength with cerebellar dysfucntion? why or why not
yes bc it is just dealing with coordination not strength
if there is cerebellar dysfunction of the vestibulocerebellum then what will we see
nystagmus
unsteadiness , truncal axtaxia m disquilibrium
what is nystagmus
bouncy eye movement
if there is cerebellar dysfunction of the cerebrocerebellum then what will we see
ataxic finger movement
dysarthria
what is dysarthria
slurring of speech
which two cerebellar dysfucntion will have dysarthia present
cerebrocerebellum and spinocerebellum
if there is cerebellar dysfunction of the spinocerebellum then what will we see
dysarthia
scanning/explosive speech
limb ataxia
loss of check/ rebound
movement decompositoin
what is scanning / explosive speech
ataxia of speech
limb ataxia includes what
dysdiadokinesia
dysmetria (action and intention tremor)
what is it called when someone has problems with rapid alternating movements
dysdiadokinesia
what is the term for the tendency to undershoot.overshoot when moving to a target
dysmertria
what is action tremor
shaking of limb during movement
what is intention tremor
tremor worsens closer to target
dysmetria tends to ocur due to delays in __ burst of acitivity and in ____ ability to brake
agonist
antagonists
what is loss of check/rebound
quick removal of resistance casues exaggerated response
what is movement decomposition
attempting to move 1 joint at a time
whcih ataxia is a disorder associated with cerebellar lesions ; disorder contractions of agonist and antagonist muscles
cerebellar ataxia
someone with cerebellar ataxia lacks the normla coordination between what
movements at different joints
what is sensory ataxia
when the posterior column medial lemniscal pathway is distrupted
the cerebellum has ___ and ____ functions
feedback and feedforward
at cellular level , ___ fibers can selectivelt causes long term ___ in synapses between ___ fibers and ___ cells that are simultaneously being activated by __- fibers
climbing
depression
parallel
purkinje
climbing
evidence present that ___ also occurs at deep cerebllar nuclei
plasticity
motor learning allows for better ___ control of movement by reduction of __ that require slower feedback mechanisms to improve movement
feedforward
errors
describe the motor learning with prime glasses and how someone with cerebellar dysfunction reacts
When a person has errors induced through wearing prism glasses, errors in dart throwing match amount of prism angle but person is able to adapt and become accurate
* When prism glasses are removed, person initially has new errors but can quickly readapt
* If person has cerebellar dysfunction, they have very difficult time learning to correct these errors
describe the motor learning with walking on a split belt treadmill and how someone with cerebellar dysfunction reacts
Requires person to move 1 leg quicker than other
* Normal person learns to adjust to regain symmetry of steps
* Person with cerebellar dysfunction can improve stepping but cannot achieve symmetry
